{"id":"DEBIAN-CVE-2026-71847","details":"Ruby JSON is a JSON implementation for Ruby. From 2.20.0 until 2.21.2, Ruby's JSON native C extension clears the consumed JSON::ResumableParser input buffer but leaves state.start, state.cursor, and state.end pointing into released storage. When partial_value reconstructs an incomplete object containing duplicate keys, the duplicate-key warning path calls cursor_position, which dereferences those stale pointers. This results in a heap-use-after-free and can terminate the Ruby process. An attacker who can supply JSON stream data to an application using JSON::ResumableParser may cause process termination when the application calls partial_value on incomplete attacker-controlled input containing duplicate object keys. This issue has been fixed in version 2.21.2.","modified":"2026-09-19T23:00:20.861938445Z","published":"2026-08-07T19:18:53.807Z","upstream":["CVE-2026-71847"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-71847"}],"affected":[{"package":{"name":"ruby-json","ecosystem":"Debian:12","purl":"pkg:deb/debian/ruby-json?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.15.2+dfsg-1","2.18.1+dfsg-1","2.19.1+dfsg-1","2.19.2+dfsg-1","2.19.4+dfsg-1","2.19.9+dfsg-1","2.21.1+dfsg-1","2.21.2+dfsg-1","2.6.3+dfsg-1","2.7.2+dfsg-1","2.7.6+dfsg-1","2.9.1+dfsg-1","3.0.2+dfsg-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-71847.json"}},{"package":{"name":"ruby-json","ecosystem":"Debian:13","purl":"pkg:deb/debian/ruby-json?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.15.2+dfsg-1","2.18.1+dfsg-1","2.19.1+dfsg-1","2.19.2+dfsg-1","2.19.4+dfsg-1","2.19.9+dfsg-1","2.21.1+dfsg-1","2.21.2+dfsg-1","2.9.1+dfsg-1","3.0.2+dfsg-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-71847.json"}},{"package":{"name":"ruby-json","ecosystem":"Debian:14","purl":"pkg:deb/debian/ruby-json?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.21.2+dfsg-1"}]}],"versions":["2.15.2+dfsg-1","2.18.1+dfsg-1","2.19.1+dfsg-1","2.19.2+dfsg-1","2.19.4+dfsg-1","2.19.9+dfsg-1","2.21.1+dfsg-1","2.9.1+dfsg-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-71847.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}